Public Works and Environmental Services Alert:

Fats, Oils and Grease (FOG)

Properly handling of Fats, Oils and Grease (FOG) is important to minimize impacts to the environment and maintenance of the sanitary sewer and storm water systems. FOG should be kept out of both the sanitary sewer and storm drains.

What is FOG?

Fats, Oils and Grease are also known as FOG, which comes from food such as cooking oil, lard, shortening, meat fats, sauces, gravy, mayonnaise, butter, ice cream and soups. Sink, dishwasher, hood and floor cleaning wastewaters and food scraps may also be sources of FOG. FOG can either be liquid or solid and may turn viscous or solid as it cools in the underground sewer.

View Notices and Best Practices.

FOG can pollute the environment!

When not disposed of properly, FOG can cause blockages in the sanitary sewer which can result in sewer backups inside a restaurant or spew wastewater from sewer manholes onto private property and the streets. Leaking and overfilled outdoor grease bins can contaminate stormwater with FOG. These backups, leaks and overflows then pollute our streams, the Potomac River and the Chesapeake Bay.

FOG can cause costly repairs!

FOG can create acidic conditions that can corrode or dissolve concrete or iron sewer pipes. Wastewater overflowing out of sewers can potentially “wash out” roads, contaminate groundwater and pollute our environment. Dischargers of FOG may be held liable for cleanup and repair costs related to sanitary sewer damage, backups and overflows.

Best way to dispose of FOG

Learn to control the disposal of FOG during food preparation, cleanup and kitchen maintenance. Wipe off dishes, pots, pans and cooking utensils before rinsing or washing. Collect waste cooking oils for recycling. Residents and Businesses can dispose of cooking oil any day during Household Hazardous Waste hours at one of the county disposal facilities at the I-66 Transfer Station or I-95 Landfill Complex. Only cooking oil (remains a liquid at room temperature) is accepted, not fats and grease. DO NOT pour cooking oil into the motor oil recycling tanks. Acceptable types of cooking oils include vegetable, peanut, canola, olive, and deep fryer oils. "Can the Grease" and dispose of it in the trash.

How can you control FOG damage?

To control the disposal of FOG during food preparation, cleanup and kitchen maintenance, wipe off dishes, pots, pans and cooking utensils before rinsing or washing. Collect waste cooking oils in grease barrels and schedule the pickup of the barrels before they are full. Install a grease trap (typically inside) or grease interceptor (typically outside) to trap the FOG before it enters the county sewer lines. Check the depth of grease and food solids in the trap/interceptor regularly. Grease traps and interceptors must be cleaned by restaurant staff or a licensed sewage handler. This is required by Fairfax County Code Chapter 67.1, Article 3. Schedule a clean out by a licensed sewage handler before the combined depth layer of the floating FOG and settled solids total more than 25 percent of the operating depth of the grease unit on the outlet side of the tank. The operating depth is the depth from the water level at the outlet pipe to the bottom of the tank.

Track the performance of your grease trap/grease interceptor!

Keep a record of the cleanout dates, the depths of the floating FOG layer and settled solids in the grease tank, approximate volume removed, and the name of the employee/licensed sewage handler who cleaned the grease tank. Post the maintenance log near the sink or maintain it in a file. This is required by Fairfax County Code Chapter 67.1, Article 3. Fairfax County inspectors will periodically check the record during inspections.

Control greasy wash water and leaky bins

Don't dump greasy wash water outdoors where it can run into a storm drain. Distance grease bins from storm drains to the extent that it is practical and keep grease bins closed. Clean up leaks and spills around grease bins promptly (not allowing wash water into storm drains), routinely check grease bins for leaks, and schedule regular pickups for proper disposal of FOG from grease bins.